Sifting Through the Subatomic Wreckage

Smashing protons together in search of the secrets to the universe at the Large Hadron Collider (LHC) near Geneva, Switzerland, yields enormous amounts of data—on the scale of all the information contained on the social networking site Facebook. Deciding which of those collisions are important and which can be ignored is an immense undertaking where the University of Oregon high-energy physics team has taken a leading role, explains James Brau, Philip H. Knight Professor of Natural Science and director of the UO Center for High Energy Physics.

In order to sift through the wreckage of interactions, which occur at a rate of hundreds of millions per second, the UO team developed hardware and software algorithms that ignored a million collisions for every one that was saved.

“It’s a search of precious golden needles buried somewhere in the haystack,” says Brau, the 2012 Presidential Research Lecturer. “If you don’t do this right, you can throw away the babies with the bath water.”

Brau and the UO team have been working on what’s been described as the largest science experiment in the world, the search for the elusive Higgs Boson particle. Through their work on the ATLAS experiment—a particle physics experiment at the European Organization for Nuclear Research (CERN) laboratory exploring the fundamental nature of matter and the basic forces that shape our universe—the team played an important role in what could prove to be the scientific discovery of a lifetime.

The Higgs Boson made international headlines in July of 2012 when scientists working at the Swiss collider announced that they had found evidence for the socalled “God particle.” The details of the discovery were published in September 2012.

Scientists are not ready to say they’ve definitely found the Higgs Boson. Brau is quick to note that the data only gives a rough measure of the features of this new particle. But so far, it looks for all the world like the Higgs Boson, which has been a missing cornerstone of modern physics for years despite its theoretical status.

The Higgs Boson is the last missing piece of the Standard Model, a theoretical foundation for modern physics that offers deep cosmic explanations. The Higgs Boson is believed to provide the mechanism for generating mass in other fundamental particles and is key to understanding the structure of the universe. The particle is named after the Scottish physicist Peter Higgs who proposed its existence in 1964 and the Indian physicist Satyendra Nath Bose who earlier developed the theory of particles with integer spin (0, 1, 2, and so on), known as bosons.

The Higgs Boson, Brau says, also explains electromagnetism’s relationship to the weak nuclear force that is responsible for radioactive decay. And it leads to deeper theories about dark matter, dark energy, and other mysteries of the universe.

“We have no idea of the potential applications or what the eventual practical implications might be,” Brau says. “But its significance in our understanding of the universe cannot be overstated.”

The Higgs Boson could have unexpected consequences, says Brau, drawing a parallel with James Clerk Maxwell’s 1873 discovery that electricity and magnetism are both regulated by the same force. Years later came radio, television, microwaves, radar, and thermal imaging.

The UO team working on the Switzerland-based experiment includes faculty members David Strom, Eric Torrence, and Ray Frey, as well as UO postdocs and students. Strom, as “trigger coordinator,” has been leading the responsibility for deciding when to capture data after interesting collisions at the ATLAS experiment.

Recent UO doctoral student graduates Jacob Searcy and Andreas Reinsch have studied collisions involving other particles. Searcy mapped the rates at which top quarks emerge from collisions and Reinsch sought out microscopic black holes.

UO physicists are also part of a worldwide collaboration developing the design and technology for the next great global physics experiment, the International Linear Collider. It will be capable of measuring properties of the Higgs Boson with even greater precision. Such precision is needed, Brau said, for new discoveries that will help shed light on dark matter, extra dimensions of space, and other unexplained phenomena.